Use of an alcohol hybrid to modify the rheology of polyethoxylated alcohol sulfates

ABSTRACT

In one embodiment, a polyethoxylated alcohol sulfate composition is provided which includes a polyethoxylated alcohol sulfate, such as sodium laureth ether sulfate (SLES), water, a mono-alcohol, and a polyol. The two alcohols form a synergistic blend, enabling a significant reduction of the viscosity of the polyethoxylated alcohol sulfate composition. Also provided is an embodiment of a method for modifying the rheology of polyethoxylated alcohol sulfate by use of a mono-alcohol and a polyol simultaneously. Finally provided is an embodiment of a detergent composition which is prepared by use of the polyethoxylated alcohol sulfate composition described herein, in addition to other commonly known ingredients.

FIELD OF THE INVENTION

The present invention relates to a method for modifying the rheology ofa high viscous compound. In particular, the invention relates to amethod for reducing viscosity of a polyethoxylated alcohol sulfate byadding an alcoholic hybrid as diluents. The present invention alsorelates to compositions comprising such diluents and a polyethoxylatedalcohol sulfate.

BACKGROUND OF THE INVENTION

Sodium laureth ether sulfate (SLES), also known as sodium lauryl ethersulfate, is an anionic detergent and surfactant widely used in manylaundry detergent products and personal care products. Its chemicalformula is CH₃(CH₂)₁₁(OCH₂CH₂)_(n)OSO₃Na, wherein n may be 2 or 3.Commercial SLES typically has three ethoxyl groups (i.e., n=3) in thechemical formula.

SLES belongs to the genus of polyethoxylated alcohol sulfates, i.e.,alkyl ether sulfates (AES) or alkyl polyethoxylate sulfates, having thefollowing Formula (I):R′—O—(C2H4O)n-SO3M′  (I)wherein R′ is a C8-C20 alkyl group, n is from 1 to 20, and M′ is asalt-forming cation, preferably, R′ is C10-C18 alkyl, n is from 1 to 15,and M′ is sodium, potassium, ammonium, alkylammonium, oralkanolammonium.

SLES is an inexpensive and effective at cleaning and emulsification.However, neat (i.e., 100%) SLES is difficult to use because it has ahigh viscosity. Moreover, SLES is a non-Newtonian fluid, meaning thatits viscosity is variable based on applied stress or force, which makesit even more difficult to handle SLES.

As such, commercial SLES is supplied as a blend of SLES (60%), ethanol(12%), water (22%), alcohol ethoxylate 3EO (5%), and sodium sulfite(1%). The addition of ethanol and other solvents into SLES reduces theviscosity of the raw material and enables it to be easily flowable andprocessable at manufacturing plants.

However, ethanol has a low flash point (i.e., 16.60° C.) below averageroom temperature. According to the industry standards, for volatilesolvents (e.g., ethanol), if the flash point is below a certain value(e.g., average room temperature), the raw material has to be shipped asa hazardous material and it also needs to be stored in a “bomb-proof”room just in case it flashes and causes an explosion. The inclusion of12 parts ethanol makes the resulting SLES/ethanol blend a potential firehazard during shipping, handling and batching with the SLES/ethanolblend, in particular on an industrial scale.

There is a need for an improved supply of SLES which not only has animproved rheology, but has a better fire safety profile. Preferably, theSLES supply contains less low flash point solvent, compared to thecurrent commercial SLES raw material. More preferably, the SLES supplycan be easily prepared either in situ (e.g., during a process ofpreparing laundry detergent or personal care products) or in advance(e.g., by preparing a stock supply of SLES).

BRIEF SUMMARY OF THE INVENTION

The inventors have unexpectedly found that a polyol and a mono-alcohol,when both were added into a polyethoxylated alcohol sulfate, such assodium laureth ether sulfate (SLES), significantly reduces the viscosityof the polyethoxylated alcohol sulfate to a manageable level and enablesit to be handled easily. Experimental data generated by the inventorsshow that a synergistic effect on the viscosity reduction has occurredby using the two different alcohols to modify the rheology of apolyethoxylated alcohol sulfate. Advantageously, the invention allowsthe reduction of the amount of a flammable alcohol needed to handle apolyethoxylated alcohol sulfate properly at manufacturing plants, whichin turn, enables a safer material handling and final product batching.

In one aspect, the present invention provides a polyethoxylated alcoholsulfate composition which has an improved rheology. The term “animproved rheology” used herein refers to a reduced viscosity level ofthe polyethoxylated alcohol sulfate composition, as compared to theviscosity level of neat polyethoxylated alcohol sulfate. An improvedrheology allows the polyethoxylated alcohol sulfate composition to bereasonably flowable and processable during manufacturing processes.

The polyethoxylated alcohol sulfate composition may consist essentiallyof a polyethoxylated alcohol sulfate having Formula (I), water, amono-alcohol, and a polyol,R′—O—(C2H4O)n-SO3M′  (I)wherein R′ is a C8-C20 alkyl group, n is from 1 to 20, and M′ is asalt-forming cation, preferably, R′ is C10-C18 alkyl, n is from 1 to 15,and M′ is sodium, potassium, ammonium, alkylammonium, oralkanolammonium.

According to some embodiments, the polyethoxylated alcohol sulfate isSLES in an amount ranging from about 20% to about 80%, from about 25% toabout 75%, from about 30% to about 70%, from about 35% to about 65%,from about 40% to about 60%, from about 45% to about 55%, from about 40%to about 45%, or about 42%, by weight of the polyethoxylated alcoholsulfate composition. The polyethoxylated alcohol sulfate composition canthus be called SLES composition or SLES blend.

In some embodiments, water is in an amount ranging from about 5% toabout 35%, from about 10% to about 30%, from about 15% to about 25%,from about 17% to about 22%, about 18%, about 19%, about 20%, or about21%, by weight of the polyethoxylated alcohol sulfate composition.

According to some embodiments of SLES compositions, SLES may be providedas a premix of neat SLES and water, which can be called SLES premix. Apreferred SLES premix consists of SLES and water in a ratio of 7:3 byweight.

It has been discovered that the addition of a polyol alone to an SLESpremix does not reduce the viscosity of the SLES premix, and to thecontrary, it may increase the viscosity. Additionally, the addition of asmall amount of a mono-alcohol (e.g., ethanol) alone to an SLES premixreduces the viscosity of SLES only to some extent. However, when ahybrid of a mono-alcohol and a polyol is added to SLES, the viscosity ofSLES is reduced significantly, much greater than the sum of theviscosity reductions caused by the mono-alcohol alone and by polyolalone.

The synergistic effect allows the use of less mono-alcohol in the SLEScomposition to reduce viscosity of the SLES composition to a desiredlevel. Suitable mono-alcohols may include those having a low flashpoint, easily flammable, and low molecular weight alcohol. Thus, the useof less mono-alcohol improves the safety profile of the SLEScomposition.

According to some embodiments, the mono-alcohol is present in an amountranging from about 1% to about 3%, from about 3% to about 6%, from about6% to about 9%, from about 9% to about 12%, or from about 12% to about15%, by weight of the SLES composition. According to some embodiments,the mono-alcohol amount is not more than 12%, more preferably, not morethan 6%, by weight of the SLES composition.

According to one embodiment, the mono-alcohol may be selected from agroup consisting of ethanol, isopropyl, propanol, butanol, pentanol,hexanol, heptanol, and octanol, and a mixture thereof. Preferably, themono-alcohol is ethanol.

According to another embodiment, the polyol is selected from a groupconsisting of polyethylene glycol (PEG), glycerine, propylene glycol(PPG), glycol ethers, 2-methyl 1,3-propanediol, 1,3-propanediol,1,5-pentanediol, glycerin, hexylene glycol, and mixtures thereof.Preferably, the polyol is PEG, glycerine, and propylene glycol. Morepreferably, the polyol is a low Mw polyethylene glycol. Most preferably,the polyol is PEG 100, PEG 200, PEG 300, PEG 400, PEG 500, PEG 600, or acombination thereof; the most preferred one is PEG 400. Asconventionally known, the number 400 indicates the average molecularweight of Mw.

According to a further embodiment, the SLES composition does not includeany additional component or solvent other than SLES, water, themono-alcohol, and the polyol. According to yet another embodiment, theSLES composition may further include one or more components selectedfrom alcohol ethoxylate, and sodium sulfite.

According to one embodiment, the polyol and the mono-alcohol have aweight ratio ranging from about 1:5 to about 5:1, preferably, from about2:1 to about 3:1; and more preferably, about 3:1.

According to another embodiment, an SLES premix and the polyol have aweight ratio ranging from about 20:1 to about 1:1; preferably, fromabout 10:2 to about 10:3; and more preferably, about 10:3.

According to a further embodiment, an SLES premix and the mono-alcoholhave a weight ratio ranging from about 60:1 to about 1:1; preferablyfrom about 10:1 to about 10:2; and more preferably, about 10:1.

According to yet another embodiment, the weight of an SLES premix and acombined weight of the mono-alcohol and the polyol have a ratio rangingfrom about 15:1 to about 1:1; preferably, from about 10:4 to about 10:3;and more preferably, about 10:4.

In another aspect, the present invention provides a process forpreparing a polyethoxylated alcohol sulfate composition with an improvedrheology. The process comprises the step of blending a polyethoxylatedalcohol sulfate with water, a mono-alcohol and a polyol, wherein thepolyethoxylated alcohol sulfate having Formula (I) and is in an amountranging from about 20% to about 80%, from about 25% to about 75%, fromabout 30% to about 70%, from about 35% to about 65%, from about 40% toabout 60%, from about 45% to about 55%, from about 40% to about 45%, orabout 42%, by the total weight of the polyethoxylated alcohol sulfatecomposition. In some embodiments, the polyethoxylated alcohol sulfatecomposition consists essentially of polyethoxylated alcohol sulfatecomposition, water, the mono-alcohol, and the polyol. In preferredembodiments, the polyethoxylated alcohol sulfate is SLES, and theresulting composition prepared by the above process can thus be calledSLES composition or SLES blend.

In some embodiments, water is in an amount ranging from about 5% toabout 35%, from about 10% to about 30%, from about 15% to about 25%,from about 17% to about 22%, about 18%, about 19%, about 20%, or about21%, by weight of the polyethoxylated alcohol sulfate composition.

According to some embodiments of the SLES composition, SLES may beprovided as a premix of neat SLES and water, which can be called SLESpremix. A preferred SLES premix consists of SLES and water in a ratio of7:3.

According to one embodiment, the SLES composition does not include anyadditional component or solvent other than SLES, water, a mono-alcohol,and a polyol. However, according to another embodiment, the SLEScomposition may further include one or more components selected fromalcohol ethoxylate, and sodium sulfite.

According to one embodiment, the mono-alcohol may be selected from agroup consisting of ethanol, isopropyl, propanol, butanol, pentanol,hexanol, heptanol, and octanol, and a mixture thereof. Preferably, themono-alcohol is ethanol.

According to some embodiments, the mono-alcohol is present in an amountranging from about 1% to about 3%, from about 3% to about 6%, from about6% to about 9%, from about 9% to about 12%, or from about 12% to about15%, by weight of the SLES composition. The mono-alcohol amount is notmore than 12%, more preferably, not more than 6%, by weight of the SLEScomposition.

According to another embodiment, the polyol is selected from a groupconsisting of polyethylene glycol (PEG), glycerine, propylene glycol(PPG), glycol ethers, 2-methyl 1,3-propanediol, 1,3-propanediol,1,5-pentanediol, glycerin, hexylene glycol, and mixtures thereof.Preferably, the polyol is PEG, glycerine, and propylene glycol. Morepreferably, the polyol is a low Mw polyethylene glycol, such as PEG 400.

According to one embodiment, the polyol and the mono-alcohol have aweight ratio ranging from about 1:5 to about 5:1, preferably, from about2:1 to about 3:1; and more preferably, of about 3:1.

According to another embodiment, an SLES premix and the polyol have aweight ratio ranging from about 20:1 to about 1:1; preferably, fromabout 10:2 to about 10:3; and more preferably, of about 10:3.

According to a further embodiment, an SLES premix and the mono-alcoholhave a weight ratio ranging from about 60:1 to about 1:1; preferablyfrom about 10:1 to about 10:2; and more preferably, of about 10:1.

According to yet another embodiment, the weight of an SLES premix and acombined weight of the mono-alcohol and the polyol have a ratio rangingfrom about 15:1 to about 1:1; preferably, from about 10:4 to about 10:3;and more preferably, of about 10:4.

In some embodiments, an SLES premix is blended with the mono-alcoholfirst before blended with the polyol. In other embodiments, themono-alcohol and the polyol are mixed first, which allows thepreparation of a stock of the alcohol hybrid if needed, before furthermixed the alcohol hybrid with the SLES premix.

In a further aspect, the present invention provides a detergent productby incorporating the polyethoxylated alcohol sulfate composition with animproved rheology, as described previously.

The detergent composition comprises:

(a) at least one nonionic surfactant, such as an alcohol ethoxylate, inan amount of about 10% to about 30%, about 15% to about 25%, or about20% to about 25%, by weight of the detergent composition;

(b) a polyethoxylated alcohol sulfate blend, such as an SLES blend, andoptionally another anionic surfactant, in an amount of about 8% to about28%, about 12% to about 25%, about 15% to about 22%, or about 18% toabout 22%, by weight of the detergent composition; wherein thepolyethoxylated alcohol sulfate blend consists essentially of apolyethoxylated alcohol sulfate, a mono-alcohol, water, and a polyol.

(c) water in an amount of about 8% to about 20%, about 12% to about 25%,about 15% to about 22%, or about 18% to about 22%, by weight of thedetergent composition.

In some embodiments, the types of SLES, water, mono-alcohol, and polyolsuitable for use in the SLES blend and the relative weight ratiosthereof, are the same as the SLES blend, which have been describedpreviously. Thus, detailed information will not be repeated.

One advantage of the present invention is that because a polyol has beenintroduced by the SLES blend, no polyol may be needed to be separatelyadded during the preparation to the detergent composition, unless thedetergent composition is desirably in need of another polyol, or in anamount more than what have been provided via the SLES blend.

In other embodiments, the detergent composition further comprises anenzyme, a fatty acid, a fragrance composition, a color care agent, apolymer dispersant agent, an anti-disposition agent, a softening agent,or a combination thereof.

The detergent composition may be provided as a liquid stored in aplastic bottle. It may also be enclosed in pouches made from awater-soluble polymer film to provide a unit dose form detergentproduct.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1. is a graph showing the rheology profiles of various SLES blends,as measured across a shear rate from 0.41 to 10 l/s.

DETAILED DESCRIPTION OF THE INVENTION

As used herein, “a,” “an,” or “the” means one or more unless otherwisespecified.

The term “or” can be conjunctive or disjunctive.

The terms “container”, “pouch”, “pack”, “pac”, “unit dose”, and “singledose” can be used interchangeably and can have one or two ormulti-compartment (i.e., multi-chamber).

The terms “blend(s)” and “composition(s)” are used interchangeably.

The terms “solvent,” “solvents,” and “solvent system,” mean a liquid orliquids used to dissolve or solvate other chemicals. In some cases,materials can also be dispersed within the solvent (i.e., TitaniumDioxide in water). In other cases, a solvent (i.e., solvent A) caninitially exist as a solid and then be dissolved within solvent B, sosolvent A can then act as a solvent itself (i.e., PEG 3350 in water). Asused herein, the terms “solvent,” “solvents,” and “solvent system,” donot include neutralization agents, such as, e.g., triethanolamine,monoethanolamine, and sodium hydroxide.

The term in a singular or plural form can mean both singular and pluralforms. For example, “textile” or “textiles” may mean both textiles andtextile; and “encapsulate” or “encapsulates” may mean both encapsulateand encapsulates.

The term “about” includes the recited number ±10%. For example, “about10” means 9 to 11.

The phrase “substantially free of” means that a composition containslittle no specified ingredient/component, such as less than about 1 wt%, 0.5 wt %, or 0.1 wt %, or below the detectable level of the specifiedingredient. For example, the phrase “substantially free of a sulphatesurfactant” refers to a liquid composition of the present invention thatcontains little or no sulphate surfactant.

As used herein, the “%” described in the present invention refers to theweight percentage unless otherwise indicated.

Unless stated otherwise, molecular weight of a polymer refers to weightaverage molecular weight.

The word “mono-alcohol” refers to a compound having only one hydroxylgroup and having no other functional groups.

The word “polyol” refers to a compound having two or more hydroxylgroups and having no other functional groups.

The invention will now be described in details using SLES as an example.However, a person of ordinary skill in the art would understand that, inaddition to reduce viscosity of SLES, the present invention isapplicable to reduce viscosity of other polyethoxylated alcohol sulfateshaving the formula, R′—O—(C2H4O)n-SO3M′, wherein R′ is a C8-C20 alkylgroup, n is from 1 to 20, and M′ is a salt-forming cation, preferably,R′ is C10-C18 alkyl, n is from 1 to 15, and M′ is sodium, potassium,ammonium, alkylammonium, or alkanolammonium.

SLES Compositions with an Improved Rheology

In one aspect, the present invention provides an SLES composition withan improved rheology profile which allows the SLES composition to beflowable and processable, suitable for manufacturing processes.

The SLES composition in accordance with the present invention consistsessentially of SLES, water, a mono-alcohol, and a polyol. SLES may bepresent in an amount ranging from about 20% to about 80%, from about 25%to about 75%, from about 30% to about 70%, from about 35% to about 65%,from about 40% to about 60%, from about 45% to about 55%, from about 40%to about 45%, or about 42%, by weight of the SLES composition.

In some embodiments, water is in an amount ranging from about 5% toabout 35%, from about 10% to about 30%, from about 15% to about 25%,from about 17% to about 22%, about 18%, about 19%, about 20%, or about21%, by weight of the polyethoxylated alcohol sulfate composition.

According to some embodiments of SLES compositions, SLES may be providedas a premix of neat SLES and water. A preferred SLES premix consists ofSLES and water in a ratio of 7:3.

Mono-alcohols suitable for the present invention include those that haveC1 to C6 mono-hydroxyl group and are in liquid or gel, preferably liquidform at room temperature. Preferably, the mono-alcohol does not createenvironmental and/or health hazards. In some embodiments, themono-alcohol may be selected from a group consisting of ethanol,isopropyl, propanol, butanol, pentanol, hexanol, heptanol, and octanol,and a mixture thereof. Preferably, the mono-alcohol is selected from agroup consisting of ethanol, isopropyl, propanol, butanol, and a mixturethereof. More preferably, the mono-alcohol is ethanol.

Polyols suitable for the present invention include those that have twoor more hydroxyl groups and are in liquid or gel, preferably liquid format room temperature. In some embodiments, the polyol is selected from agroup consisting of polyethylene glycol (PEG), glycerine, propyleneglycol (PPG), glycol ethers, 2-methyl 1,3-propanediol, 1,3-propanediol,1,5-pentanediol, glycerin, hexylene glycol, and mixtures thereof.Preferably, the polyol is PEG, glycerine, and propylene glycol. Morepreferably, the polyol is a low Mw polyethylene glycol, such as PEG 400.

The inventors have unexpectedly noticed that, upon adding a polyol tothe SLES/mono-alcohol blend, the viscosity level of SLES has beensignificantly reduced. It is known that a small molecule alcohol with alow boiling point (e.g., ethanol) may be used as a diluent, optionallywith other solvents (e.g., water), to modify the rheology profile ofSLES. For example, commercial SLES is supplied as a blend of SLES (60%wt), ethanol (12% wt), water (22% wt), alcohol ethoxylate 3EO (5% wt),and sodium sulfite (1% wt), in order to provide a flowable andprocessable form of SLES. The more ethanol added to SLES, the lower ofthe viscosity level of the resulting SLES composition.

It is known that a polyol may serve as a solvent for detergent productsin general. But it is not known that a polyol could be used forviscosity adjustment for SLES. In fact, adding a polyol alone to SLESundesirably increase the viscosity of SLES. It is further unknown that apolyol and a mono-alcohol, when both are added to SLES, would cause asynergistic effect on the reduction of viscosity of SLES, meaning thatthe resulting viscosity reduction is much greater than the sum of theviscosity reductions caused by the addition of a mono-alcohol alone toSLES and by the addition of a polyol alone to SLES.

The present invention advantageously allows the use of less low flashingpoint mono-alcohol in the SLES composition while still providing SLES ina form with a desirable viscosity level. Without wishing to be bound bytheory, it is believe that the addition of a polyol to anSLES/mono-alcohol blend synergistically enlarges the viscosity reductioneffect caused by a small amount of alcohol, leading to an overallgreater viscosity reduction.

According to some embodiments, the mono-alcohol is present in an amountranging from about 1% to about 3%, from about 3% to about 6%, from about6% to about 9%, from about 9% to about 12%, or from about 12% to about15%, by weight of the SLES composition. In some embodiments, themono-alcohol amount is less than 12%, more preferably, less than 6%, byweight of the SLES composition.

According to some embodiments, the polyol and the mono-alcohol have aweight ratio ranging from about 1:5 to about 5:1, from about 1:4 toabout 4:1, from about 1:3 to about 3:1, or from about 1:2 to about 2:1.According to other embodiments, the polyol and the mono-alcohol have aweight ratio ranging from about 1:5 to about 1:4, from about 1:4 toabout 1:3, from about 1:3 to about 1:2, from about 1:2 to about 1:1,from about 1:1 to about 1:2, from about 2:1 to about 3:1, from about 3:1to about 4:1, or from about 4:1 to about 5:1. According to furtherembodiments, the polyol and the mono-alcohol have a weight ratio ofabout 1:5, about 1:4, about 1:3, about 1:2, about 1:1, about 2:1, about3:1, about 4:1, or about 5:1; preferably, about 2:1, about 3:1.

According to some embodiments, an SLES premix and the polyol have aweight ratio ranging from about 20:1 to about 1:1, from about 15:1 toabout 2:1, from about 10:1 to about 3:1, about 5:1 to about 4:1, about5:4, about 5:3, or about 5:2; preferably, about 5:3. According to otherembodiments, an SLES premix and the polyol have a weight ratio rangingfrom about 10:1 to about 10:5, from about 10:2 to about 10:4, about10:1, or about 10:3; preferably from about 10:2 to about 10:3; and morepreferably, about 10:3.

According to some embodiments, an SLES premix and the mono-alcohol havea weight ratio ranging from about 60:1 to about 1:1, from about 50:1 toabout 2:1, from about 40:1 to about 3:1, about 30:1 to about 4:1, fromabout 20:1 to about 5:1, from about 15:1 to about 5:1, about 10:1 toabout 5:1, about 15:1, about 12.5:1, about 10:1, about 7.5:1, about 5:1;preferably from about 10:1 to about 10:2; and more preferably, about10:1.

According to further embodiments, the weight of an SLES premix and acombined weight of the mono-alcohol and the polyol have a ratio rangingfrom about 15:1 to about 1:1, from about 14:1 to about 2:1, from about13:1 to about 3:1, about 12:1 to about 4:1, from about 11:1 to about5:1, from about 10:1 to about 6:1, about 9:1 to about 7:1. According toyet further embodiments, the weight of an SLES premix and a combinedweight of the mono-alcohol and the polyol have a ratio of about 10:5,about 10:4, about 10:3, about 10:2, about 10:1; and more preferably,about 10:4.

According to a further embodiment, the SLES composition does not includeany additional component or solvent other than SLES, water, themono-alcohol, and the polyol. According to yet another embodiment, theSLES composition further includes one or more components selected from agroup consisting of alcohol ethoxylate, and sodium sulfite.

Process for Preparing SLES Blends

In accordance with the present invention, a process for preparing anSLES composition with an improved rheology comprising: blending SLESwith water, a mono-alcohol, and a polyol.

SLES is present in an amount ranging from about 20% to about 80%, fromabout 25% to about 75%, from about 30% to about 70%, from about 35% toabout 65%, from about 40% to about 60%, from about 45% to about 55%,from about 40% to about 45%, or about 42%, by the total weight of theSLES composition.

In some embodiments, water is in an amount ranging from about 5% toabout 35%, from about 10% to about 30%, from about 15% to about 25%,from about 17% to about 22%, about 18%, about 19%, about 20%, or about21%, by weight of the SLES composition.

According to some embodiments of SLES compositions, SLES may be providedas a premix of neat SLES and water. A preferred SLES premix consists ofSLES and water in a ratio of 7:3.

In some embodiments, the SLES composition does not include anyadditional component or solvent other SLES, water, a mono-alcohol, and apolyol. In other embodiments, the SLES composition may include one ormore components selected from a group consisting of alcohol ethoxylate,and sodium sulfite.

The types and the amounts of the mono-alcohol and the polyol, includingpreferred embodiments and the relative weight ratios among themono-alcohol, the polyol, and the SLES premix, that are suitable for theprocess are substantially the same as those described in the section,SLES Compositions With An Improved Rheology. Thus, details of theformulation will not be repeated.

In some embodiments, the SLES premix is blended with the mono-alcoholfirst before blended with the polyol. In other embodiments, the polyoland the mono-alcohol are mixed first to prepare a stock solution beforesuch stock solution is then mixed with the SLES premix. In furtherembodiments, all of the components are added and mixed altogether.

The mixing step can be conducted by any conventional equipment,following conventional methods. The components may be heated tofacilitate the mixing, followed by cooling. Preferably, all thecomponents are mixed until they become homogenous.

Detergent Compositions

A further aspect of the present invention provides a detergentcomposition which comprises the SLES blend described herein.

In one embodiment, the detergent composition comprises:

(a) at least one nonionic surfactant, such as an alcohol ethoxylate, inan amount of about 10% to about 30%, about 15% to about 25%, or about20% to about 25%, by weight of the detergent composition;

(b) an SLES blend, and optionally another anionic surfactant, in anamount of about 8% to about 28%, about 12% to about 25%, about 15% toabout 22%, or about 18% to about 22%, by weight of the detergentcomposition; wherein the SLES blend consists essentially of SELS, amono-alcohol, water, and a polyol;

(c) water in an amount of about 8% to about 20%, about 12% to about 25%,about 15% to about 22%, or about 18% to about 22%, by weight of thedetergent composition.

Nonionic Surfactants

Examples of nonionic surfactants suitable for the present inventioninclude, but are not limited to, polyalkoxylated alkanolamides,polyoxyalkylene alkyl ethers, polyoxyalkylene alkylphenyl ethers,polyoxyalkylene sorbitan fatty acid esters, polyoxyalkylene sorbitolfatty acid esters, polyoxyethylene polyoxypropylene alkyl ethers,polyoxyalkylene castor oils, polyoxyalkylene alkylamines, glycerol fattyacid esters, alkylglucosamides, alkylglucosides, alkylamine oxides,amine oxide surfactants, alkoxylated fatty alcohols, or a mixturethereof. In some embodiments, the nonionic surfactant is alcoholethoxylate (AE), alcohol propoxylate, or a mixture thereof. In otherembodiments, the nonionic surfactant is AE.

The AE may be primary and secondary alcohol ethoxylates, especially theC₈-C₂₀ aliphatic alcohols ethoxylated with an average of from 1 to 20moles of ethylene oxide per mole of alcohol, and more especially theC₁₀-C₁₅ primary and secondary aliphatic alcohols ethoxylated with anaverage of from 1 to 10 moles, or from 3 to 8 moles of ethylene oxideper mole of alcohol.

Exemplary AEs are the condensation products of aliphatic C₈-C₂₀,preferably C₈-C₁₆, primary or secondary, linear or branched chainalcohols with ethylene oxide. In some embodiments, the alcoholethoxylates contain 1 to 20, or 3 to 8 ethylene oxide groups, and mayoptionally be end-capped by a hydroxylated alkyl group.

In one embodiment, the AE has Formula (II):R₂—(—O—C₂H₄—)_(m)—OH  (II)wherein R₂ is a hydrocarbyl group having 8 to 16 carbon atoms, 8 to 14carbon atoms, 8 to 12 carbon atoms, or 8 to 10 carbon atoms; and m isfrom 1 to 20, or 3 to 8.

The hydrocarbyl group may be linear or branched, and saturated orunsaturated. In some embodiments, R₂ is a linear or branched C₈-C₁₆alkyl or a linear group or branched C₈-C₁₆ alkenyl group. Preferably, R₂is a linear or branched C₈-C₁₆ alkyl, C₈-C₁₄ alkyl, or C₈-C₁₀ alkylgroup. In case (e.g., commercially available materials) where materialscontain a range of carbon chain lengths, these carbon numbers representan average. The alcohol may be derived from natural or syntheticfeedstock. In one embodiment, the alcohol feedstock is coconut,containing predominantly C₁₂-C₁₄ alcohol, and oxo C₁₂-C₁₅ alcohols.

One suitable AE is Tomadol® 25-7 (available from Air Product). Othersuitable AEs include Genapol® C200 (available from Clariant), which is acoco alcohol having an average degree of ethoxylation of 20.

Anionic Surfactants

In some embodiments, the anionic surfactant is a polyethoxylated alcoholsulfate, such as those sold under the trade name CALFOAM® 303 (PilotChemical Company, California). Such materials, also known as alkyl ethersulfates (AES) or alkyl polyethoxylate sulfates of Formula (I), such asSLES, as described before.

In other embodiments, the anionic surfactant may be linear alkylbenzenesulfonic acid (LAS) or a salt thereof, alkyl ethoxylated sulphate, alkylpropoxy sulphate, alkyl sulphate, or a mixture thereof. Linearalkylbenzenesulfonate (LAS) is a water-soluble salt of a linear alkylbenzene sulfonate having between 8 and 22 carbon atoms of the linearalkyl group. The salt can be an alkali metal salt, or an ammonium,alkylammonium, or alkanolammonium salt. In one embodiment, the LAScomprises an alkali metal salt of C₁₀-C₁₆ alkyl benzene sulfonic acids,such as C₁₁-C₁₄ alkyl benzene sulfonic acids.

However, in further embodiments, the detergent compositions aresubstantially free of LAS.

SLES Blend

As described herein, the SLES blend consists essentially of SLES, water,a mono-alcohol, and a polyol. The types and the amounts of thecomponents of the SLES blend and the relative weight ratios thereof, arethe same as what have described in the section, SLES Compositions WithAn Improved Rheology. Thus, details of the formulation will not berepeated.

Optionally, Other Ingredients in the Detergent Compositions

In some embodiments, the detergent composition may comprise a cationicsurfactant, an ampholytic surfactant, a zwitterionic surfactant, ormixtures thereof.

In other embodiments, the detergent composition may comprise a fattyacid. Suitable fatty acid may be any fatty acid having formula:R₃—C(O)OH, wherein R₃ is a C₅-C₂₁ linear or branched aliphatic group.Preferably, the R₃ is a C₁₃-C₂₁ linear or branched aliphatic group. In apreferred embodiment, the fatty acid is dodecanoic acid (also known ascoconut fatty acid).

In further embodiments, the detergent composition may comprise afragrance composition, a color care agent, a soil releasing polymer, ananti-disposition agent, a softening agent, or a combination thereof. Itmay also comprise a whitening agent, a brightening agent, acolor/texture rejuvenating agent, a bleaching catalyst, a bleachingagent, a bleach activator, a buffer, a surfactant stabilizer, aneutralization agent, a builder, an enzyme, a dye (colorant), adispersing agent, a defoamer, an anticorrosion agent, a deodorizingagent, a preservative, a bittering agent, and/or a biocidal agent.

Unit Dose

The detergent composition may be filled in plastic bottles to providebottled products. It may also be enclosed in pouches to provide unitdose detergent pacs, where the pouches are formed from a water-solubleor water-dispersible film material, which fully encloses the detergentcomposition. The detergent composition may be in the form of a solutionor a suspension, although a solution is preferred. In some embodiments,the container comprises at least two compartments, with one compartmentreceiving the liquid composition and other compartment(s) receivingadditional compositions. Each compartment may have the same or differentcompositions. The additional compositions may be liquid, solid, gel, ormixtures thereof.

The water-soluble or water-dispersible film material may be selectedfrom the group consisting of polyvinyl alcohol (PVOH), polyvinyl acetate(PVA), film forming cellulosic polymer, polyacrylic acid,polyacrylamide, polyanhydride, polysaccharide, polyvinyl pyrrolidone,polyalkylene oxide, cellulose, cellulose ether, cellulose ester,cellulose amide, polyvinyl acetate, polycarboxylic acid and salt,polyaminoacid, polyamide, natural gums, polyacrylate, water-solubleacrylate copolymer, methylcellulose, carboxymethylcellulose sodium,dextrin, ethylcellulose, hydroxyethyl cellulose, maltodextrin,polymethacrylate, polyvinyl alcohol copolymer, and hydroxypropyl methylcellulose (HPMC), and a mixture thereof. In preferred embodiments, thewater-soluble or water-dispersible film material is selected frompolyvinyl alcohol or polyvinyl acetate.

As stated earlier, the present invention is not limited to SLES, thepresent invention is applicable to the reduction of viscosity of otherpolyethoxylated alcohol sulfates, i.e., alkyl ether sulfates (AES) oralkyl polyethoxylate sulfates, having the following formula (I):R′—O—(C2H4O)n-SO3M′  (I)wherein R′ is a C8-C20 alkyl group, n is from 1 to 20, and M′ is asalt-forming cation, preferably, R′ is C10-C18 alkyl, n is from 1 to 15,and M′ is sodium, potassium, ammonium, alkylammonium, oralkanolammonium.

Accordingly, as also described in the Brief Summary of the Invention,the present invention also provides (1) a polyethoxylated alcoholsulfate blend consisting essentially of polyethoxylated alcohol sulfate,water, a mono-alcohol, and a polyol; (2) a method for preparing thepolyethoxylated alcohol sulfate blend; and (3) a detergent compositionor a unit dose detergent product comprising at least one nonionicsurfactant, the polyethoxylated alcohol sulfate blend and a solventsystem.

The types and the amounts of the components suitable for use in theinvention covering a polyethoxylated alcohol sulfates are substantiallythe same as those used in the embodiments, wherein the anionicsurfactant is SLES. Thus, details of the information will not berepeated. A person of ordinary skill in the art would understand thescope of the present invention covers all the embodiments, wherein SLESis simply substituted with a polyethoxylated alcohol sulfate of Formula(I). Details of the embodiments having a polyethoxylated alcohol sulfateblend with an improved rheology will not be elaborated herein because itwould be substantially a repeat.

EXAMPLES

The following examples are intended to further illustrate the inventionand are not intended to limit the invention in any way.

Example 1

Preparation of SLES Compositions

In order to compare differences in rheology of SLES as a result of theaddition of ethanol and/or at least one of other alcohols, SLEScompositions of eight formulas were prepared: Formula 1 includes 70parts SLES and 30 parts water only; Formula 2 includes 60 parts amixture of SLES and water (SLES:water=7:3), 12 parts ethanol, and no apolyol; Formula 3 includes 60 parts SLES and water mixture(SLES:water=7:3), 6 parts ethanol, and no polyol; Formula 4 includes 60parts SLES and water mixture (SLES:water=7:3), no ethanol, and 12 partsPEG 400; Formula 5 includes 60 parts SLES and water mixture(SLES:water=7:3), 6 parts ethanol, and 12 parts PEG 400; Formula 6includes 60 parts SLES and water mixture (SLES:water=7:3), 6 partsethanol, and 12 parts propylene glycol (PG); Formula 7 includes 60 partsSLES and water mixture (SLES:H2O=7:3), 6 parts ethanol, and 12 partsglycerine (Gly); and Formula 8 includes 60 parts SLES and water mixture(SLES:water=7:3), 6 parts ethanol, and 18 parts PEG 400. Thecompositions were prepared at a laboratory scale of 60 g of each finalSLES composition.

SLES composition of Formula 1 was prepared by mixing neat SLES andwater. SLES compositions of Formulas 2 to 8 were prepared generally asfollows: 1) providing a mixing container with an overhead stirrer; 2)adding water (if applicable) to the container; 3) adding SLES:water(7:3), ethanol (if applicable) and PG/Gly/PEG 400 (if applicable), andoptionally other ingredients, in the container and mixing all of theingredients with the stirrer until a homogenous mixture is obtained.During the process, each composition was checked for clumps which werebroken as required. The mixing process can be conducted at an elevatedtemperature to facilitate the mixing by heating the components in thecontainer directly or indirectly (i.e., heating up the container).Finally, the SLES compositions were cooled to room temperature.

Example 2

Rheology Measurement of the SLES Compositions

Rheology measurements were conducted using an AR2000-EX Rheometer with atest method of increasing the shear rate from 0.41 to 10 l/s over 5minutes at 20° C. with a geometry cone of 40 mm, 1:59:49(degree:min:sec), and a truncation gap of 52 microns (cone is partnumber 511406.901). Viscosities (Pa·S) of the SLES Blend Formulationsprepared in Example 1 were measured and reported in Table 1. “SLES*” inthe Table of the application stands for a mixture of SLES and water witha ratio of 7:3.

TABLE 1 Formula 2 3 4 5 8 1 SLES*:Etha- SLES*:Etha- SLES*:Etha-SLES*:Etha- 6 7 SLES*:Etha- SLES* nol:(PG/Gly/ nol:(PG/Gly/ nol:PEGnol:PEG SLES*:Etha- SLES*:Etha- nol:PEG Shear only, no PEG) = PEG) = 400= 400 = nol:PG = nol:Gly = 400 = Rate alcohol(s) 60:12:0 60:6:0 60:0:1260:6:12 60:6:12 60:6:12 60:6:18 (1/s) Viscosity (Pa · S) 0.41 95.5100.429 55.070 121.800 1.511 4.487 25.100 1.086 0.75 49.480 0.294 28.73071.860 0.916 2.059 11.140 0.646 1.08 32.980 0.232 18.620 53.320 0.6961.209 7.257 0.482 1.41 24.730 0.221 13.910 44.090 0.565 0.841 5.6460.425 1.73 19.840 0.196 11.310 38.570 0.507 0.662 4.674 0.368 2.0616.660 0.176 9.707 34.820 0.449 0.602 4.111 0.337 2.39 14.550 0.1768.653 32.240 0.440 0.494 3.790 0.318 2.72 12.920 0.190 7.903 30.0700.431 0.433 3.528 0.316 3.06 11.770 0.201 7.339 28.350 0.419 0.409 3.3190.316 3.39 10.640 0.195 6.842 26.940 0.422 0.387 3.061 0.324 3.71 9.7080.194 6.469 25.590 0.441 0.390 2.950 0.329 4.05 9.031 0.208 6.157 24.5500.430 0.398 2.828 0.319 4.37 8.616 0.220 5.860 23.710 0.420 0.402 2.7400.313 4.71 8.195 0.246 5.591 22.630 0.411 0.347 2.651 0.306 5.03 7.6840.253 5.284 21.620 0.419 0.307 2.593 0.303 5.37 7.263 0.250 5.039 20.7600.416 0.311 2.509 0.292 5.70 6.970 0.274 4.883 20.290 0.397 0.312 2.4470.291 6.03 6.687 0.296 4.733 20.040 0.393 0.287 2.382 0.297 6.36 6.2760.294 4.603 19.660 0.393 0.277 2.319 0.287 6.68 6.086 0.290 4.463 19.4200.380 0.279 2.263 0.282 7.02 5.888 0.280 4.273 19.180 0.380 0.264 2.2030.284 7.35 5.652 0.272 4.125 18.970 0.378 0.266 2.170 0.280 7.68 5.5860.306 4.008 18.670 0.372 0.256 2.141 0.285 8.01 5.383 0.287 3.917 18.2100.374 0.260 2.080 0.279 8.34 5.295 0.283 3.788 17.860 0.366 0.256 2.0720.281 8.67 5.093 0.266 3.698 17.520 0.368 0.258 2.048 0.281 8.99 4.9230.281 3.611 17.450 0.358 0.262 2.050 0.282 9.32 4.756 0.276 3.534 17.2300.361 0.258 1.993 0.281 9.66 4.613 0.267 3.456 16.900 0.352 0.259 1.9880.281 9.99 4.483 0.295 3.346 16.450 0.356 0.255 1.992 0.278

FIG. 1 is a graph showing the rheology changes of SLES as a result ofthe addition of an alcohol hybrid, based on the data of Table 1.

As shown in FIG. 1, the addition of ethanol reduced the viscosity ofSLES, however, the extent of reduction depended on the ratio of SLES andethanol in the composition. When the SLES premix and ethanol had aweight ratio of 60 parts to 12 parts (Formula 2), the viscosity of theSLES blend was reduced significantly, from 32,980 cP (the SLES premix,Formula 1) to 0.232 cP at a shear rate of 1.08 l/s. When the SLES premixand ethanol had a weight ratio of 60 parts to 6 parts (Formula 3), theviscosity was only reduced to 18,620 cP from 32,980 cP (the SLES premix,Formula 1) at a shear rate of 1.08 l/s.

FIG. 1 shows that the addition of a polyol, alone to the SLES premix didnot reduce the viscosity of SLES. To the contrary, it may increase theviscosity. For example, the viscosity of the resulting SLES premix andPEG in a weight ratio of 60 parts to 12 parts was increased to 53,320 cPfrom 32,980 cP (the SLES premix, Formula 1) at a shear rate of 1.08 l/s.

However, when PEG 400 was added to an SLES blend having the SLES premixand ethanol, it greatly improved the rheology of the SLES blend.

When an additional 12 parts of PEG 400 was added to the SLES blendhaving the SLES premix and ethanol in a ratio of 60 parts:6 parts, theviscosity of the SLES blend (Formula 5) further dropped from 18,620 cPto 696 cP at a shear rate of 1.08 l/s. When an additional 18 parts ofPEG 400 was added to the SLES blend having the SLES premix and ethanolin a ratio of 60 parts:6 parts, the viscosity of the SLES blend (Formula8) further dropped from 18,620 cP to 482 cP at a shear rate of 1.08 l/s.

The use of propylene glycol or glycerine to substitute PEG 400 in ablend of SLES premix, ethanol, and PEG 400 also showed a decrease inviscosity of SLES, although the extent of decrease is not as much aswhen PEG was used. Nevertheless, the he SLES blends, i.e., premix SLES,ethanol, and PG/Gly/PEG 400, all supply SLES with a viscosity that is amanageable level from a process point of view.

The rheology of compositions of Formulas 5 and 8 showed a clear trendthat the more PEG 400 added to the SLES blend, the lower viscosity ofthe SLES blend. Additionally, less ethanol is required to reduceviscosity of the SLES composition if PEG 400 is added.

FIG. 1 shows that there existed a synergic effect in lowering theviscosity level of SLES as a resulting of adding both ethanol and apolyol, such as PEG 400, propylene glycol, and glycerine. For example,when only PEG 400 (12 parts) is added to the SLES premix, the rheologyof the resulting composition of Formula 4 became worse (more viscous)than that of the composition of Formula 1. When only ethanol (6 parts)is added to the SLES premix, the rheology of the resulting compositionof Formula 3 only improved modestly. However, when both PEG 400 (12parts) and ethanol (6 parts) were added to the SLES premix, the rheologyof the resulting composition of Formula 5 showed a significantimprovement compared to that of the composition of Formula 1.

Example 3

Preparation of Laundry Detergent Compositions Comprising SLES

Laundry detergent compositions using the SLES blend, as set forth inTable 2, were prepared by following conventional methods of preparation.Instead of using highly viscous SLES, a flowable and processable SLESblend was used during the manufacturing process.

Composition 1 Composition 2 Composition 3 Description (% wt) (% wt) (%wt) C12-C15 Alcohol 23.1 23.1 23.1 Ethoxylate 7EO PEG 400 18.5 0 0 SLESBlend 18.72 0 0 (60 parts SLES premix, 12 parts ethanol) SLES Blend 020.26 0 (60 parts SLES premix, 6 parts ethanol, 12 parts PEG 400) SLESBlend 0 0 21.85 (60 parts SLES premix, 6 parts ethanol, 18 parts PEG400) Glycerine 9 9 9 Propylene Glycol 7 7 7 Bases 1.5 1.5 1.5 Fatty Acid4 4 4 Enzymes 1.5 1.5 1.5 Other Ingredients 1.1 1.1 1.1 Water 13.6 1210.5 Polymeric 2 2 2 Dispersant Total 100 100 100

As shown in Compositions 2 and 3, one advantage of using the SLES blendhaving PEG 400 as a co-diluent is that, depending on the amount of PEG400 needed in a detergent composition, no PEG may be needed to beseparately added during the preparation to the detergent composition.Thus, the present invention creates a way to introduce PEG 400 into thedetergent product without the need of a dedicated PEG 400 ingredienttank because PEG 400 is provided in the SLES blend.

While at least one exemplary embodiment has been presented in theforegoing detailed description of the invention, it should beappreciated that a vast number of variations exist. It should also beappreciated that the exemplary embodiment or exemplary embodiments areonly examples, and are not intended to limit the scope, applicability,or configuration of the invention in any way. Rather, the foregoingdetailed description will provide those skilled in the art with aconvenient road map for implementing an exemplary embodiment of theinvention, it being understood that various changes may be made in thefunction and arrangement of elements described in an exemplaryembodiment without departing from the scope of the invention as setforth in the appended claims and their legal equivalents.

What is claimed is:
 1. A polyethoxylated alcohol sulfate blendconsisting essentially of: a polyethoxylated alcohol sulfate havingFormula (I):R′—O—(C2H4O)n-SO3M′  (I) wherein R′ is C10-C18 alkyl, n is from 1 to 15,and M′ is sodium, potassium, ammonium, alkylammonium, oralkanolammonium, ethanol, a polyol chosen from the group consisting ofpolyethylene glycol, propylene glycol, glycerine, and combinationsthereof, and water; wherein the polyethoxylated alcohol sulfate ispresent in an amount ranging from about 20% to about 80% by weight ofthe blend; and wherein the polyethoxylated alcohol sulfate, the ethanol,and the polyol are present in a weight ratio of actives of 7:1:2 to7:1:3.
 2. The polyethoxylated alcohol sulfate blend of claim 1, whereinthe polyethoxylated alcohol sulfate is sodium laureth ether sulfate(SLES).
 3. The polyethoxylated alcohol sulfate blend according to claim1, wherein the polyol is PEG
 400. 4. The polyethoxylated alcohol sulfateblend according to claim 1, consisting of the polyethoxylated alcoholsulfate, the water, the ethanol, and the polyol.
 5. The polyethoxylatedalcohol sulfate blend according to claim 1, having a viscosity of lessthan 100 Pa·S over a shear rate between 0.41 to 10 1/s at 20° C.
 6. Thepolyethoxylated alcohol sulfate blend according to claim 1, having aviscosity of less than 26 Pa·S over a shear rate between 0.41 to 10 1/sat 20° C.
 7. The polyethoxylated alcohol sulfate blend of claim 1,wherein the polyethoxylated alcohol sulfate is sodium laureth ethersulfate and the polyol is polyethylene glycol
 400. 8. Thepolyethoxylated alcohol sulfate blend of claim 1, wherein thepolyethoxylated alcohol sulfate is sodium laureth ether sulfate, thepolyol is propylene glycol and the sodium laureth ether sulfate, theethanol, and the propylene glycol are present in a weight ratio ofactives of 7:1:2.
 9. The polyethoxylated alcohol sulfate blend of claim1, wherein the polyethoxylated alcohol sulfate is sodium laureth ethersulfate, the polyol is glycerine and the sodium laureth ether sulfate,the ethanol, and the glycerine are present in a weight ratio of activesof 7:1:2.
 10. The polyethoxylated alcohol sulfate blend of claim 4,wherein the polyethoxylated alcohol sulfate is sodium laureth ethersulfate and the polyol is polyethylene glycol
 400. 11. Thepolyethoxylated alcohol sulfate blend of claim 4, wherein thepolyethoxylated alcohol sulfate is sodium laureth ether sulfate, thepolyol is propylene glycol and the sodium laureth ether sulfate, theethanol, and the propylene glycol are present in a weight ratio ofactives of 7:1:2.
 12. The polyethoxylated alcohol sulfate blend of claim4, wherein the polyethoxylated alcohol sulfate is sodium laureth ethersulfate, the polyol is glycerine and the sodium laureth ether sulfate,the ethanol, and the glycerine are present in a weight ratio of activesof 7:1:2.
 13. The polyethoxylated alcohol sulfate blend of claim 1,wherein the polyol is chosen from the group consisting of propyleneglycol, glycerine, and combinations thereof.